Details/description:
HISTORICAL BACKGROUND: Presumably built in 1230 A.D. (cf. "Capitulum seu Rotulus Decimarum", one of the most ancient documents in the ecclesiastical history of Parma), from the mid 15th century onwards the original structure underwent various transformations, particularly the construction of side colonnades for the use of the numerous pilgrims. Around the year 1700, a radical transformation of the internals is believed to have taken place and is still visible today, which hid, for many long years, the series of paintings and frescoes which had formerly embellished the walls of the central nave and the entire vault system. The greatest damage of the ground/foundation system was found on the side nave structures.
CLIENT: Diocese of Fidenza.
FUNDING: Euro 800,000.00 (Cariparma, CEI, Emilia Romagna Regional Authorities, Parish of Pellegrino P.se, Diocese of Fidenza).
USE: Place of Worship.
CONFIGURATION OF THE DAMAGE: obvious cracks due to differential subsidence running towards the side naves that were built at a later date.
LITHOLOGICAL CONTEXT (from Z=0): in the surface part (from 0.00 to 1.50 m), presence of filling materials with very high resistivity, followed by non cohesive materials with a medium resistivity ranging from 5 to 38 Ohm*m and hence not without a fine silt/sand matrix with considerable variations in water saturation and/or compaction in order to reach the most conductive portions which can be characterized both by a fluid saturation with a higher salt content and by the presence of a fine matrix (clay, silt).
FOUNDATION STRUCTURE: surface foundation in stone masonry.
EXTENT OF PROCEDURE: approx. 35 lm on two facades.
DIAGNOSTIC SYSTEM: survey of crack pattern, Georadar, penetrometric tests.
DIAGNOSTIC CRITERIA: overlapping analysis of all the data measured.
DESCRIPTION OF PROCEDURE: Compaction and consolidation of the foundation bed of the structure. First of all, investigative diagnostics were carried out in order to identify both the masses of soil underneath the building footprint in order to get a clearer picture of the portions of ground within the load-bearing mass area deemed to be the cause of the subsidence, and of any archeological sub-structures that could potentially interfere with the procedure. We then prepared injection pipes targeted towards the masses of soil presenting the deficit and subject to subsidence. The injections were then carried out in the quantities laid down according to the data available in literature, between the foundation curb and the ground with slow expansion resin Ti(25°C)>40 sec.
